• Bulletin of the Korean Chemical Society
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• v.19 no.10
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• pp.1080-1083
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• 1998

An efficient method for construction of 2-arylfiirans has been developed by ceric(IV) ammonium nitratemediated oxidative cycloaddition of cyclic and acyclic 1,3-dicarbonyl compounds to several alkynes. Reactions of 1,3-cyclohexanedione, 1,3-cyclopentanedione, and 2,4-pentanedione with several alkynes furnish 2-arylfurans in 26-75% yields. Extension of this technology to more complex 4-hydroxy-2-quinolone and 3-hydroxy-lH-phenalen-l-one with phenylacetylene also affords furoquinolinone and ftirophenalenone derivative in moderate yields. Reaction of 4-hydroxycoumarins with phenylacetylene give linear and angular furocoumarin derivatives as a mixture of regioisomer in good yields. The mechanistic pathway for the formation of 2-arylfurans has been also described.

• YAKHAK HOEJI
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• v.48 no.3
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• pp.202-206
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• 2004

New asymmetric dimers, N,N'-dialkyl-4'-hydroxy-4-oxo-2,2',3,3'-tetrahydro-2,2'-diphenyl-4,4'-quinolones 3a-f were synthesized through the dehydration and dea1coholation of N-alkylanilines and ethyl benzoylacetate. Dimers 3a-f were identified by NMR, IR and GC-MS. A series of dimer 3a-f has been synthesized using acid-catalyzed one-pot reaction that involved the condensation, cyc1ization and dimerization. Similarly, the 6,6'-methoxy (or 7,7'-methoxy) substituted dimers were prepared from N-alkyl-meta-(or para)-anisidines. Formation of dimers was undertaken with p-toluenesulfonic acid (p-TSA) at 90∼11$0^{\circ}C$ in toluene for 2∼6 hours over the Dean-Stark apparatus.

• The Korean journal of internal medicine
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• v.33 no.6
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• pp.1070-1078
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• 2018

Vibrio vulnificus is a gram-negative bacterium that can cause serious, potentially fatal infections. V. vulnificus causes three distinct syndromes: an overwhelming primary septicemia caused by consuming contaminated seafood, wound infections acquired when an open wound is exposed to contaminated warm seawater, and gastrointestinal tract-limited infections. Case-fatality rates are higher than 50% for primary septicemia, and death typically occurs within 72 hours of hospitalization. Risk factors for V. vulnificus infection include chronic liver disease, alcoholism, and hematological disorders. When V. vulnificus infection is suspected, appropriate antibiotic treatment and surgical interventions should be performed immediately. Third-generation cephalosporin with doxycycline, or quinolone with or without third-generation cephalosporin, may be potential treatment options for patients with V. vulnificus infection.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.344.2-344.2
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• 2002

Sophoricoside analogs are natural isoflavonoids isolated from fruits of Sophora japonica L. and exhibited an inhibitory effect on IL -5. Many synthetic variations on isoflavonoids has been reported. but relatively few examples of quinolone analogs have been described. As part of our endeavor to develop novel and effective IL-5 inhibitor, we have synthesized azaisoflavones by cyclization of the key intermediate, 2'-aminochalocone obtained from substituted aniline. The synthesized azaisoflavones were evaluated for their inhibitory activtities on IL-5 comparing with natural Sophoricoside analogs. None of the azaisoflavones showed promixing inhibitory effects In the assay. Nevertheless. assay data Indicated that 5.7-phenolic hycroxy groups on the A-ring and alkyl subsitiuent on N1 seemed to play an importnt role in the IL-5 bioassay.

• Microbiology and Biotechnology Letters
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• v.51 no.4
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• pp.555-558
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• 2023

Staphylococcus aureus is a prominent multidrug-resistant pathogen known for its resistance to a variety of antibiotics. To combat this, a wide range of antibiotics, including quinolones, is utilized. While the efficacy of quinolones against S. aureus has been established, the rise in quinolone-resistant strains, particularly in methicillin-resistant S. aureus (MRSA), has necessitated a shift in their usage patterns. Genomic sequencing plays a crucial role as it offers insights into the genetic mechanisms of resistance. Thus, we report the complete genome sequence of an oxolinic acid-resistant strain of S. aureus isolated from sweet potato leaves, a crop commonly cultivated in Korea.

• Korean Journal of Clinical Pharmacy
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• v.22 no.1
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• pp.55-64
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• 2012

The quinolones are broad-spectrum antibiotics and enhanced antimicrobial activity has extended the use of the quinolones beyond the traditional indications for quinolone antibiotics in the treatment of urinary tract infections. The quinolones are effective in a wider variety of infectious diseases, including skin and respiratory infections. Because of their excellent safety and tolerability, they have become popular alternatives to penicillin and cephalosporin derivatives in the treatment of various infections. A retrospective study was performed to evaluate efficacy and safety of IV quinolones for inpatient use. Total 117 patients who administerd quinolones for longer than 3 continuous days at community hospital from October 1st, 2008 to December 31st, 2008 were reviewed. The criterias for drug evaluation were included the validation of indication, outcome, dosage and side effects. In the results, ciprofloxacin 13 (total 93), levofloxacin 3 (total 59) and moxifloxacin 2 (total 19) cases were not met the criterias based on the culture results. Major indications were pneumonia (ciprofloxacin 16.3%, levofloxacin 67.8%, moxifloxacin 84.2%), urinary tract infection (ciprofloxacin 44.1%), skin infection (ciprofloxacin 7.5%, levofloxacin 20.3%, moxifloxacin 10.5%), intra-abdominal infection (ciprofloxacin 10.8%, moxifloxacin 5.3%), etc.. In the results of quinolone monotherapy, the frequencies were each ciprofloxacin 74.2%, levofloxacin 50.8% and moxifloxacin 47.4%. In the results of dosage validation, the validities were each ciprofloxacin 54.8%, levofloxacin 94.9% and moxifloxacin 100.0%. In the results of duration validation, the validities were each ciprofloxacin 59.1%, levofloxacin 78.0% and moxifloxacin 89.5%. Adverse drug reactions were reported for total 49 cases and those were gastrointestinal tract effects including nausea, vomiting, diarrhea and central nervous system effects including headache, dizziness. In summary, the quinolones appropriately used for hospitalized patients based on this study. A focused approach emphasizing "correct use of quinolones" may reduce development of antimicrobial resistance and maximize class efficacy. Consequently, correct use of antibiotics will contribute to decrease medical expenses for person and community.

• Applied Microscopy
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• v.36 no.2
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• pp.93-99
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• 2006

Gemifloxacin is a synthetic fluoroquinolone antimicrobial agent that exhibits potent activity against most Gram-negative and Gram-positive organisms, and has a comparatively low chondrotoxic potential in immature animals. This study examined the effects of gemifloxacin on the Achilles tendons in immature Sprague-Dawley rats treated by oral intubation once daily for 5 consecutive days from postnatal week 4 onward at doses of 0 (vehicle), and 600mg/kg body weight Ofloxacin was used for comparison. The Achilles tendon sperimens were examined by electron microscopy. In comparison with the vehicle-treated controls, there were ultrastructural changes in all samples from the gemifloxacin- and ofloxacin-treated rats. Degenerative changes were observed in the tenocytes, and the cells that detached from the extracellular matrix were recognizable. The degree of degenerative changes and the number of degenerated cells in the Achilles tendon were significantly higher in the treated group than in the control group. Moreover, among the quinolone treated groups, these findings were more significant in the ofloxacin treated group, and less significant in the gemifloxacin treated group. It is unclear what these findings mean with respect to the possible risk ill juvenile patients treated with gemifloxacin or other quinolones. However, these results show that gemifloxacin causes fewer changes in the connective tissue structures.

• Microbiology and Biotechnology Letters
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• v.36 no.4
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• pp.360-365
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• 2008

For the screening of residual antibiotics in foods, bioassays and microbiological inhibitor tests are commonly applied. These methods are tested by the various susceptibility of bacteria against different kinds of antibiotics. However, the sensitivity of bioassay is generally insufficient to detect some residual antibiotics at level of interest. This study was performed to investigate the detection limit of variable antibiotics of the bioassay and to improve the sensitivity to some antibiotics. The sensitivity of bioassay using Bacillus megaterium ATCC 9885, B. subtilis ATCC 6633, B. cereus ATCC 11778 and Geobacillus stearothermophilus ATCC 10149 was low in the detection of macrolides, quinolones, chloramphenicol, and monensin. On the contrary, Micrococcus luteus ATCC 9341 showed high sensitivity to macrolides and Escherichia coli ATCC 11303 was highly sensitive to quinolones and aminoglycosides. Consequently, both strains would be useful to improve sensitivity of bioassay with a wide detection range.

• Journal of Yeungnam Medical Science
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• v.10 no.1
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• pp.135-143
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• 1993

The susceptibilities of 45 clinical isolates of bacteroides frogilis to cefaclor, ciproflxacin and imipenem were determined by new method, E-test (AB Bidisk, Solna, Sweden) and were compared with those from conventional agar dilution method by using brain heart infusion, Mueller-Hinton and Wilkins Chalgren agar plates. And the susceptibility of 60 clinical isolates of Bacteroides fragilis group (B. fragilis 45 strains, B. distasonis 6 strains, B. ovatus 5 strains, B. thetaiotaomicron 4 strains) to 5 quinolones (ciprofloxacin, enoxacin, norfloxacin, ofloxacin, pefloxacin) were determined by in vitro agar dilution method. Compared with agar dilution MICs for B. fragilis 45 strains, 90.3% of E-test MICs were within ${\pm}$1 dilution of the agar dilutions, and 98.4% were within 2 dilutions. And there were little effect of different medium bases to determine MICs except Mueller-Hinton agar. On Mueller-Hinton agar, B. fragilis showed have or no growth activity. In vitro susceptibility of B. fragjlis group to quinolones, most of the test strains showed resistant patterns to quinolones except ofloxacin and there was little difference of susceptibility patterns between species of B. fragilis group.

• Journal of Life Science
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• v.16 no.5
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• pp.799-805
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• 2006

The in vitro activities of quinolones were determined with 36 strains of tetracycline- resistant, 39 strains of erythromycin-resistant, 21 strains of both resistant to tetracycline and erythromycin, and 27 strains of both susceptible to tetracycline and erythromycin of the M. pneumoniae isolates which have been isolated and classified in previous studies. The $MIC_{90}$ of moxifloxacin, levofloxacin, sparfloxacin, ofloxacin, ciprofloxacin, amikacin, and clarithromycin against 36 strains of tetracycline-resistant M. pneumoniae isolates were 0.125, 0.39, 0.125, 1.0, 1.0, 15.6, and $1.56\;{\mu}g/ml$, respectively. The $MIC_{90}$ against 39 strains of eryhtromycin-resistant M. pneumoniae isolates were 0.06, 0.39, 0.125, 1.0, 1.0, 15.6, and $25.0\;{\mu}g/ml$, respectively. The $MIC_{90}$ against 21 strains of both resistant to tetracycline and eryhtromycin of M. pneumoniae isolates were 0.125, 0.39, 0.125, 1.0, 1.0, 3.9, and $1.56\;{\mu}g/ml$, respectively. The $MIC_{90}$ against 27 strains of both susceptible to tetracycline and eryhtromycin of M. pneumoniae isolates were 0.125, 0.39, 0.125, 1.0, 1.0, 7.8, and $0.09\;{\mu}g/ml$, respectively. These result suggest that moxifloxacin, levofloxacin, and sparfloxacin of the quinolones might be promising antimicrobial agents for the treatment of tetracycline- and erythromycin-resistant M. pneumoniae infection. However, selection of ofloxacin, ciprofloxacin, and clarithromycin for the treatment of M. pneumoniae infection should be cautious decision with antimycoplasmal susceptibility test.